Calculating machine



vOCt. 4, 1949. 5,

CALCULATING MACHINE Filed May 6, 1944 3 Sheets-Sheet 1.

IN VEIY TOR.

QATTORNEY Oct. 4, 1949. v E. GRIP 2,483,459

CALCULATING MACHINE Filed May a, 1944 :5 Sheets-Sheet 2 rig- E.

I V NTOR. 54

A TTORNEY Filed May a, 1944 E. GRIP CALCULATING MACHINE 3 Sheets-Sheet 3 Patented Oct. 4, 1949 CALCULATING MACHINE Erik Grip, Atvidaberg, Sweden, assignor to Aktieholaget Facit, Atvidaberg, Sweden, a corporation of Sweden Application May 6, 1944, Serial No. 534,453 In Sweden November 80, 1942 Section 1, Public Law 690, August 8, 1946 Patent expires November 30, 1962 1 Claim.

For effecting operations of division in calculating machines, the dividend is first set into the actuator (such as a pin wheel rotor) and then the operator causes the actuator to effect one revolution to enter the dividend into the results register; that revolution is registered in the revolutions counter, on one or more numeral wheels. Thus, when the dividend is entered additively into the results register, that is by means of a positive revolution, the numeral 1 ap pears in the revolutions counter, but when the dividend is entered into the results register sub tractively, that is, by negative revolution, one or more numerals 9 appear on the numeral wheels of the revolutions counter. It is, therefore, necessary tov clear the revolutions counter, before the operation of division is continued with the divisor set in the actuator. This clearing operation necessitates an additional manipulation and may easily be forgotten, which results in errors of calculation.

It has been proposed to use special devices to render the revolutions counter inoperative, when the dividend is entered into the results register. Thus, it was proposed to use a mechanism, which is actuated manually, to displace the revolutions counter actuator (quotient tooth) laterally out of its operative position so that it does not act on the revolutions counter when the dividend is entered into the results register. tion sufiers from serious drawbacks, because for each denomination the revolutions counter actuator must be able to assume two different positions laterally of each other, and especially in calculating machines having a stationary revolutions counter and a revolutions counter act-uator movable laterally, such construction is very complicated and occupies much space.

The chief purpose of this invention is to eliminate the clearing operation of the revolutions counter generall necessary after the dividend has been entered into the results register in operations of division, in calculating machines capable of performing automatic division.

Another purpose of this invention is to disable the revolutions counter actuator automatically, when the. machine is set to automatic division and then the dividend is entered into the results register.

Another purpose of this invention is to render operations of division simpler than heretofore. Thus, in accordance with this invention, one step of operation is eliminated and the attention of the operator may be concentrated on the chief operations. The same lever that sets, the ma-.

Said construcwards,

chine to automatic division simultaneously disables the revolutions counter actuator for simple addition operations; the dividend is always ens tered by means of a simple addition operation.

Other purposes will be evident from the following specification and claim.

One embodiment of a device in accordance with the invention is illustrated in the annexed drawings.

Fig. 1 shows an end view of a device in accordance with this invention.

Fig. 2 shows a corresponding front view.

Fig. 3 shows a top view of the driving gears for the revolutions counter actuator.

Fig. 4 shows a side view of the motor-contact closing mechanism; and

Fig. 5 shows in section and on a larger scale, a detailed view of the coupling pawl mechanism.

Fig. 6 shows a perspective view of certain details controlled by the chief control lever of the machine.

Fig. '7 shows an end view of the upper parts of Fig. 1 the end wall being broken away to show the details in full.

Fig. 8 shows a side View of a detail.

In the drawings only those parts are shown which are necessary to illustrate the invention. When not otherwise expressly stated, in this specification the expressions right, left, updownwards, forward and backward are used to designate those directions, as they appear to an operator, sitting at the keyboard of the machine.

The machine illustrated in the drawings is j in its principal features constructed in accordnexed drawings is of the Odhner or pin-wheel type and has an actuator or pin wheel rotor 4 which is displaceably splined on the main shaft 5. For carrying out the operations of calculation this shaft together with the actuator 4 is 1 rotated in either direction direction or direction, as indicated by the arrows in Fig. 1)

under the control of a multiplication key or positivev multi-revolutions key I and a division key or negative multi-revolutions key 2. Said keys start the actuator 4 in the positive or in the negative direction of rotation respectively, that is, counter-clockwise and clockwise, respectively, in Fig. 1, for effecting one or more revolutions without clearing the rotor. In addition, the machine has an addition key 253 which when depressed causes the actuator 4 to efiect one positive revolution and then to be cleared automatically. In analogy a subtraction key may be provided, as described in detail in U. S. Patent No. 2,398,286.

In addition, the machine also has the control lever 28f described in said last-mentioned patent for setting the machine to automatic division and to multiplication with automatic shift to the right and to the left, respectively. This lever is shown (at 243i) in the patent just mentioned. It has a plurality of functions, but of those functions only that one is here concerned that at the setting of the control lever to automatic division said control lever displaces the shaft 228 of the revolutions counter actuator (quotient tooth) to he left in Fig. 3 (see Fig. 5 of the U. S. patent just mentioned) so that the toothed wheel 225 is coupled to the toothed wheel 223 by means of the left carrier or clutch 22:. The operation of the lever I is illustrated in Fig. 6. The control lever 255 is pivoted on a stationary journal 205 secured to the machine frame. An arm 2i3 of the control lever 23! is movable in a cam slot 254 of a lever 2i5, which is rockable on a stationary pin 2i6. A pin 233 is secured to the lever H5 and a tension spring 232 urges an arm 229 against this pin. By means of a pin 235, the arm 229 is articulately connected with a lever 225 which is rockable on a stationary pin 224. This lever has a cam 226 engaging an annular or peripheral slot in the shaft 2i'8.

When the lever 25! is set manually to its position for division (as shown in Fig. 1), the lever 25 is rocked counter-clockwise and by means of the arm 229 rocks the lever 225 counter-clockwise. This causes the cam 226 to displace the shaft 2%8 axially to its minus position (position for division), that is its extreme left position in Fig. 3, and consequently the toothed wheel 229 is coupled to the toothed wheel 223 by means of the left clutch 22!. The toothed wheel 225 is secured to the shaft 258 and consequently causes that shaft to rotate if said wheel is rotated. But the toothed wheels 222, 223 are loosely journalled on the shaft 2L8 (the toothed wheel 229 drives the tens transfer rotor for the revolutions counter).

The addition key 263 is rotatably journalled on the shaft 3M and its projection or catch 342 engages the lever or rocking arm 344 which is rotatably journalled on a stationary pin 346. This pin may, for instance, be secured to the base plate 265 of the machine frame. A tension spring 34'. pulls the lever 34A. upwards and said lever has a projection or catch 354 which acts on the multiplication key I, when the lever 344 is rocked downwards in Fig. 1 (clockwise in Fig. 2) by the addition key 223. For guiding purposes the lever 324 has a slot 558 cooperating with a stationary guiding pin 55!. The lever 344 also has a recess 552, which encloses the projection 553 of the bar 556 so that said bar follows the motion of the arm 344 in the vertical direction. In this motion the bar 554 is guided by the studs or screws 555 entering guiding slots in said bar. In its upper end this bar has a part 556 bent out laterally and passing through a recess or hole in an end wall 210 of the machine frame. The flat and 4 somewhat bevelled point 551 of that part 556 extends inwards above a coupling pawl 558.

Said pawl is rotatably journalled on a pin 558 in a slot in the oblong hub 560 of a toothed wheel 56I running freely on the main shaft 5 and permanently engaging the toothed wheel 223. In addition to the projection extending into the path of the point 551 the coupling pawl 558 also has two projections or wings 558a and 558D and is under the action of a compression spring 562 tending to rock said pawl counter-clockwise in Figs. 2 and 5 so that the wing 558a enters a slot 553 in the hub of the toothed wheel 564 secured to the shaft 5 (by means of a pin or the like). In the position shown in the drawings, that is the stopping position or position of rest of the actuator 4, the projection 55% is just opposite a slot 565 in the stationary guide 566.

The toothed wheel 564 permanently meshes with the driving toothed wheel 55? which is secured is a shaft 568 and also drives the toothed wheel 222. The shaft 558 is driven via a drivin mechanism (for instance of the type shown in U. S. Patents Nos. 2,068,899 and 2,127,102, respectively), in either direction of rotation, depending upon which of the control keys has been depressed. When the projection 558a engages the slot 563, the toothed wheel 56'! also drives the toothed wheel 223 via the toothed wheel 561, and then the wheel 223 rotates in opposite direction to the wheel 222. According as the toothed wheel 220 then is coupled with the toothed wheel 222 or the toothed wheel 223, the shaft 2 N3 of the revolutions counter actuator is caused to rotate in the same direction as the toothed wheel 222 (normal direction of rotation for addition, subtraction and multiplication) or as the toothed wheel 223 (normal direction of rotation for division), that is, in the same direction or in the opposite direction, respectively, as that of the pin wheel rotor 4.

On the lever 344 a pawl 569 is rockably journalled on the pin 352. One end of that pawl is fork-shaped and encloses a stationary pin 35] secured to the base plate 265. The recess 552 in the rocking lever 344 is so dimensioned that the pin 35! does not hinder the motion of the lever. The pawl 569 has an arm or a projection 568a extending upwards and so dimensioned that when the lever 344 is rocked clockwise (in Fig. 2) the projection 569a is rocked (also clockwise) inwards below the forward end of the locking arm 505. Said arm is journalled on the stationary shaft 35 and in its opposite end carries a pin 555a, Fig. 4, which engages a curve or a cam on a contact lever 33L Said contact lever is rockably journalled on the pin 333 and its back edge rests on the motor contacts 334. At its forward end the contact lever 33l engages the multiplication key I, and in the embodiment shown this engagement is effected via the pin 51!] secured to the contact lever.

On the end wall 512 springs 57! are secured which have the purpose of preventing the toothed wheels 222, 223 from being displaced axially, said springs passing the toothed wheels against the end walls 210 and 572.

The device described acts as follows:

The machine is set for division by setting the chief control lever 23! manually to its position of division. As is described in detail in the patent just mentioned, this sets the shaft 218 carrying the revolutions counter actuator (quotient tooth) to its extreme left position. The

dividend is now entered into the pin-wheel rotor 4, for instance by means of numeral keys, and said rotor is now tabulated to its extreme left position in well-known manner. Then the operator depresses the addition key 203 to enter the dividend into the results register (not shown). When depressed, this key 203 acts on the rocking lever 344 which then pulls the bar 554 downwards, so that the point 551 of that bar is moved downwards in Figs. 2 and 5, and it swings the coupling pawl 558 clockwise against the action of the spring 562. Thus, the projection 558a is moved out of engagement with the slot 563 and instead of it the projection 5581) engages the slot 565 in the stationary guide 556. The toothed wheel 56l is consequently now free from the driving toothed wheel 56! and is in addition locked in its position of rest (that is the stopping position or position of rest of the pin wheel rotor 4). When the key 203 is depressed, it also depresses the multiplication key I via the projection 354 and said key I then closes the contacts 334 for the current to the electric motor, via the contact lever 33L When the contact lever 31 is thus rocked clockwise in Fig. 1, it rocks the arm 505 counter-clockwise so that the front end of that arm visible in Fig. 2 is moved downwards. Simultaneously the pawl 569 has been rocked clockwise in Fig. 2, when the lever 344 follows the depressed key 203. The front end of the locking arm 5B5 extending downwards then engages the oblique (bevelled) surface at the upper end of the projection 569a of the pawl 569 so that said pawl remains locked and consequently locks the key in its depressed position, when the operator releases the addition key 203. Now the motor 4 performs one revolution in the direction and then is cleared. This causes the dividend to be entered into the results register, but the revolutions counter is not actuated, because the shaft 2! of the revolutions counter actuator is disengaged from the driving mechanism.

It is to be observed that during the entire operation of addition and the subsequent clearing of the rotor 4, the contact lever 33l in is well-known manner kept in its operative position (as described in U. S. Patent No. 2,898,286), and consequently the contact 334 remains closed. Via the locking arm 505 and the pawl 569 and the lever 344 the addition key is thus kept locked in its depressed position so that it cannot return before the operation of addition is finished. This is important for avoiding errors, because it prevents the operator from bringing the disengaged toothed wheel 5! out of position by means of repeated depressions of the addition key; as long as that key is kept depressed and locked in its depressed position, also the toothed wheel 56l is locked by the pawl 558.

When the operation of addition is finished, the addition key 203 returns to its position of rest. It is to be observed that the oblique surface of the arm 569a of the pawl 569 is so shaped that the key 203- is not locked at the return motion.

When the addition key 203 returns to its original position, the point 551 is lifted off from the pawl 558 which is now rocked counter-clockwise by the spring 562, so that the projection 558b is disengaged from the guide 566 and simultaneously the projection 558a enters the slot 563.

If the division key 2 or the multiplication key I is depressed, the bar 554 and consequently also the pawl 558 are not actuated. After the divisor has been entere into the rotor 4, the operation of division can, therefore, be finished in wellknown manner, the shaft 2l8 being driven from the toothed wheel 56! via the toothed wheel 564 and the pawl 558 and the toothed wheels SH ,223 so that the revolutions counter actuator operates in the usual manner on the revolutions counter.

It is to be observed that, if desired, numerals may be entered into the revolutions counter by means of the multiplication and division keys L2 before the beginning of the operation of division. During such entering operation the rotor 4 remains cleared.

When the chief control lever (MI) is set in either of its positions for multiplication, the shaft 218 is in its right position so that the toothed wheel 220 is coupled with the toothed wheel 222 and consequently the driving wheel 561 drives the shaft 2| 8 and the shaft 5 in the same direction of rotation.

Addition is normally effected with said chief control lever in either of its positions of multiplication, and then the number of items of addition is automatically registere in the revolutions counter which in some cases is important.

What I claim is:

In a calculating machine adapted to divide by repeated alternative addition and subtraction having an accumulator, a revolutions counter, a differential actuator, a revolutions counter actuator, and a plurality of operation control keys, in combination, drive means for said counter actuator comprising a shaft driven in synchronism with the differential actuator, an axially adjustable counter actuator shaft reversibly operable with respect to said differential actuator, a first gear train operable by said synchronously driven shaft, said gear train terminating in a first gear loosely mounted on said counter actuator shaft, a second gear train operable by said synchronously driven shaft terminating in a second gear loosely mounted on said counter actuator shaft, said second gear operating oppositely to said first gear, a coupling member fixed to said counter actuator shaft and engageable with either said first or second gear by axial adiustment of said counter actuator shaft, a disconnectable coupling pawl in said second gear train, and means controlled by one of the plurality of operation control keys for disconnecting said pawl, whereby when said coupling member is engaged with said second gear and said pawl is disconnected by operation of said control key said synchronously driven shaft will be ineffective to drive said counter actuator shaft.

ERIK GRIP.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,381,898 Andersson June 21, 1921 2,088,974 Pott Aug. 3, 1937 2,227,785 Kottman Jan. 7, 1941 2,252,621 Eichler Aug. 12, 1941 2,310,280 Friden Feb. 9, 1943 2,366,345 Machado Jan. 2, 1945 2,382,661 Pott Aug. 14, 1945 FOREIGN PATENTS Number Country Date 551,311 Great Britain Feb. 17, 1943 

